1. Field of the Invention
The present invention relates generally to stamping machines comprising at least one imprinting station of the gilding press type.
2. Prior Art
It is known that at such an imprinting station a stamp or die, which is mounted suitably movable for this purpose and the pattern of which corresponds to that of the desired impression, applies to the article to be imprinted a foil or leaf suitable for this type of impression.
The present invention relates more particularly, but not necessarily exclusively, to the case in which the articles to be imprinted are articles with a neck, for example bottles, which being made of synthetic material and thus not having per se sufficient rigidity to provide in satisfactory manner a suitable support for the stamp thereby make it necessary for their internal volume to be placed under pressure when they are being imprinted, so as to provide an abutment for said stamp.
It is thus necessary to use at the imprinting station in question two shells which, mounted movably relative to one another, are designed to mutually enclose at least the portion to be imprinted of the bottle to be imprinted and, in practice, almost the whole bottle, so as to counteract its internal pressure while it is being imprinted.
In practice, in the hitherto known machines of the type in question only one of the shells is movable and, usually, since said shells are arranged vertically on either side of the article to be imprinted, this would be the upper shell, the lower shell being firmly secured to the frame of such a machine.
This arrangement gives rise to various disadvantages.
Firstly, it is the machine frame which receives the reaction force to which the movable shell is subjected during imprinting of the article to be imprinted and, therefore, this frame has to be strengthened, to the detriment of its weight and cost.
Moreover, since the lower shell is fixed and the conveyor carrying the article-carrier supports necessarily extends at a distance therefrom, it is necessary to provide transfer means for each article to be imprinted from the article-carrier support which carries it to said lower shell, before it is imprinted, and from this lower shell to said article-carrier support after imprinting, to the detriment of the operating rhythm of the machine and its simplicity.
In French Patent No. 1,093,042, and likewise in U.S. Pat. No. 3,478,680, it is proposed to use two shells both movably mounted and thus suitable for enclosing the article to be imprinted.
However, their control means are independent, which can result in synchronization problems.
The present invention relates generally to a device which enables these disadvantages to be obviated and which, moreover, achieves further advantages.